1. Field of the Invention
The present invention relates to cutting torches and cutting tips, and more particularly to a molded insert formed of a resilient, non-metallic material which is placed into the metal head of an oxy-fuel cutting torch and allows a standard metal cutting tip to be installed leak-free into the cutting torch head.
2. Brief Description of the Related Art
Oxy-fuel cutting torches are used with cutting tips to perform cutting operations in the metalworking industry. The cutting torch conveys fuel gas and oxygen to the tip where the mixture of the two combusts at the tip exit orifices to pre-heat the metal to be cut. Pure oxygen is also discharged from the cutting tip to sever the pre-heated metal by an oxidation process.
Conventionally, oxy-fuel cutting torch heads and cutting tips have been formed from metal such as brass and copper. The use of these materials is based on their resistance to degradation by corrosion in the industrial environment, their resistance to elevated temperatures, and their ease of fabrication by standard manufacturing practices such as forging and machining. Conventional designs require that the metal cutting tip be installed into the cutting torch head and held firmly in place, in metal-to-metal contact, by means of a threaded metal tip nut. The tip nut is tightened using a wrench until it applies sufficient force on the tip to form a gas tight seal between the metal seats of the tip and the metal torch head seat. Prior cutting tips are typically made from a single piece of metal or are assembled from multiple pieces. Prior cutting tips typically rely on metal-to-metal sealing with the torch head to prevent premature mixing of oxygen and fuel in the cutting tip and torch head.
The prior art head and tip designs have several drawbacks. Cutting tips are subject to damage due to dirt, mishandling, and abuse in the industrial environment. Nicks, scratches, and dents cause the seats to leak when installed into the cutting torch head and subjected to oxygen and fuel gas under pressure. Seat leaks cause operating malfunctions such as backfiring and flashback which can be hazardous. Furthermore, the surface finish of prior metal-to-metal seals is critical, and significant cost is involved in manufacturing and maintaining torches and tips with appropriate surface finishes.